Rotor aircraft



FIG. 1 is a front view;

FIG. 2 is a rear view;

FIG. 3 is a right side view;

FIG. 4 is a left side view;

FIG. 5 is a top view;

FIG. 6 is a bottom view; and,

FIG. 7 is a bottom perspective view thereof.

CLAIM The ornamental design for a rotor aircraft, substantially as shownand described.